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Date: Wed, 30 Jun 2010 09:49:20 +0100
From: "Jan Beulich" <JBeulich@novell.com>
To: "Peter Zijlstra" <peterz@infradead.org>
Cc: <jeremy.fitzhardinge@citrix.com>, <mingo@elte.hu>, <tglx@linutronix.de>,
       "Ky Srinivasan" <KSrinivasan@novell.com>,
       <linux-kernel@vger.kernel.org>, <hpa@zytor.com>
Subject: Re: [PATCH 4/4, v2] x86: enlightenment for ticket spin locks -
	 improve yield behavior on Xen
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>>> On 30.06.10 at 10:11, Peter Zijlstra <peterz@infradead.org> wrote:
> On Tue, 2010-06-29 at 15:35 +0100, Jan Beulich wrote:
>> 
>> The (only) additional overhead this introduces for native execution is
>> the writing of the owning CPU in the lock acquire paths. 
> 
> Uhm, and growing the size of spinlock_t to 6 (or 8 bytes when aligned)
> bytes when NR_CPUS>256.

Indeed, I should have mentioned that. Will do so in an eventual
next version.

Jan